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E39 (1997 - 2003) The BMW 5-Series (E39 chassis) was introduced in the United States as a 1997 model year car and lasted until the 2004 when the E60 chassis was released. The United States saw several variations including the 525i, 528i, 530i and 540i. -- View the E39 Wiki

Hi folks, I've been sorting out a bunch of codes with my e39 recently. It's currently in the shop for a suspension overhaul, but my mechanic says it needs a new water pump and thermostat housing. While I trust him 100%, my engine trouble codes are P0170 and P1188 with MIL not ready indications of catalyst, evap, sec air, and o2 sensor.

Before I ask him to do anything with this SES light, I'm looking for opinions on what this might be indicative of? I'm somewhat hoping that simply swapping the 2 precat o2's will take care of it, but I also get the inkling it may be something else, especially with all of those MIL warnings. Help would be appreciated. Thanks!